POLYCH^TA. — BENHAM. 207 



The present specimen measures 42 mm., with a diameter 

 of 10 mm. at its broadest, which extends from about the 

 15th to 20th segments. It contains 29 segments. 



The dorsal and ventral chsetse are aUke, though the ventrals 

 are much finer, straight, thick-walled, hollow, with a simple 

 point. A few of the ventrals have a minute subapical tooth ; 

 or this may be represented by a "' step " where the tooth 

 has been worn away. 



Loc. — Off South Cape, Tasmania, 75 fathoms. 



Distribution. — New Zealand. 



Family ALCIOPID.E. 



Clenus Halodora, Greeff. 



Halodora, sp. ? 



(Plate xl., figs. 52-55 ; Plate xli., fig. 56.) 



I have no recent literature on this group, so that I am un- 

 able to compare the present worm with those previously 

 described. I attribute them to the genus Halodora, Greeff, 

 as the head does not project beyond the eyes ; the introvert 

 is without denticles, and there is no " cirriform lip " to the 

 parapodia, while the chsetse are compound. It differs from 

 H. reynaudii, Audouin & Milne-Edwards, in various respects. 



The material consists of two cephalic fragments, two tails 

 and an intermediate region of the body, belonging to one of 

 the two individuals ; the portions are much coiled, and mea- 

 surements are difficult to make with accuracy. ^ But the 

 worm seems to be about 40 mm. in length, with a diameter 

 of 1 mm. or 2 mm. over the parapodia. It is widest an- 

 teriorly where the width is 2 mm. over the eyes, and tapers 

 slowly posteriorly. 



The worm then is long and narrow, with large brown spots 

 on each segment laterally, just behind the base of the para- 

 podia ; the cephalic eye is of enormous size, and rich brown 

 in colour, the pupil faces downwards and outwards. 



Each of the anterior segments is crossed by a narrow band 

 of brown pigment, of a width about equal to the antero- 

 postericr width of a parapodium, and on the first seven or 

 eight segments it is continued from side to side, linking the 

 lateral spots ; but in the following segments it is broken in 



1. One cephalic fragment has twenty-three segments and measures 

 12 mm. in length ; one head-less fragment has fifty segments followed by 

 twenty -four very small regenerated segments. 



